This invention pertains generally to guided missiles incorporating gyroscopically stabilized elements, and particularly to arrangements for sensing the body spin rate of any such type of missile.
It is known in the art, as shown in U.S. Pat. No. 4,536,685 (which patent, assigned to the same assignee as this application, is incorporated herein by reference), that the gimbals of a gyroscopically stabilized antenna in a guided missile (hereinafter referred to simply as a missile) may be precisely controlled. Thus, as shown in the just-cited patent, a pair of phase-locked control loops may be operated in tandem in response to signals from Hall effect crystals to synchronize an electric motor driving a gyroscope to an externally generated clock signal. As a result, then, the orientation of a gyroscopically stabilized platform on which an antenna is mounted may be precisely determined.
It is highly desirable, if not essential, that the spin rate of the body of the missile also be determined. Unfortunately, as disclosed in the cited reference, there is no apparent way in which the teaching of the cited reference may be used to determine the spin rate of the body of a missile. It follows, then, that other known devices, such as accelerometers and associated circuitry, may be used to determine the desired spin rate. However, any known device and required signal processing circuitry are expensive and difficult to implement in the confines of a missile.